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userbinatoryesterday at 4:11 AM1 replyview on HN

Contrast with x86:

    add eax, ecx
    jo overflow

Replies

rwmjyesterday at 10:26 AM

Neither x86-64 nor RISC-V is implemented by running each single instruction. They both recognize patterns in the code and translate those into micro-ops. On high performance chips like Rivos's (now Meta's) I doubt there'd be any difference in the amount of work done.

Code size is a benefit for x86-64 however - no one is arguing that - but you have to trade that against the difficulty of instruction decoding.

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